There will be an NHTSA approved road legal version, per Fox News https://www.foxnews.com/auto/new-half-ton-electric-pickup-co...

They fall under the same laws as golf karts, which vary from state to state.

Short answer: They aren't, except for certain roads with speeds under 35 MPH. This isn't a "car" in the traditional sense an American would recognize, it's a cart.